ION-EXCHANGE IN ZEOLITE EU-1 .1. THE EFFECT OF SI AL RATIO/

Ion-exchange isotherms for H+, K+, Cs+, Ca2+, Sr2+, and Ba2+ exchangin g for Na+ in samples of EU-1 with a range of Si/Al ratios have been de termined. Uni-univalent exchange isotherms were independent of the Si/ Al ratio. Complete di-univalent exchange was not obtained and this has been attributed to a pair of Al atoms only being able to balance the charge on a divalent cation if they are closer than a certain distance . By comparison of the isotherm cutoffs with the calculated Al-Al dist ances, it is investigated whether it is possible to determine the loca tion of Al atoms within the framework.